Design and control of a high-acceleration precision positioning system using a novel flexible decoupling mechanism

This article presents a high-acceleration precision positioning system to improve the efficiency and precision of micro-electro-mechanical system (MEMS) packaging. The positioning system is direct driven by linear voice coil actuators (LVCAs), and the mass and inertia of the motion system are significantly reduced by using a novel flexible decoupling mechanism based on flexure hinges. The decoupling principle of the mechanism is introduced, and the flexure hinges are designed by using an analytical method. Through dynamic analysis, the stiffness and preload of the spring are determined. With the aid of finite-element method and dynamic analysis, the influences of flexure hinges on the characteristics of the positioning system are investigated. Based on the dynamic characteristics of LVCA and the developed mechanism structure, the electromechanical coupled models are established. Minimum deadbeat response control strategy with a pre-filter is implemented to control the positioning system, and the parameters of the controller are optimized. Experimental tests are carried out to examine the characteristics of the positioning system. The results show that the positioning system provides good performances and satisfies the requirements of MEMS packaging operations.